Multiple Fan Blade Angles in a Single Crossflow Fan

ABSTRACT

A fan may be provided. The fan may comprise a first plurality of vanes and a second plurality of vanes. The first plurality of vanes may be arranged substantially parallel to an axis of rotation and positioned along a first arc substantially centered on the axis of rotation. Vanes in the first plurality of vanes may be being positioned at a first angle relative to the first arc. The second plurality of vanes may be arranged substantially parallel to the axis of rotation and positioned along a second arc substantially centered on the axis of rotation. Vanes in the second plurality of vanes may be positioned at a second angle relative to the second arc. The first angle may be different than the second angle.

CROSS-REFERENCE TO RELATED APPLICATIONS

The current application is related to U.S. patent application Ser. No.13/338,287 filed on Dec. 28, 2011, entitled “Vented Fan Duct,” (AttorneyDocket No. Al214H), and U.S. patent application Ser. No. ______ filed onDec. 28, 2011, entitled “Adjusting Air Flow without Restricting a Fan,”(Attorney Docket No. Al226H), which are hereby incorporated by referencein its entirety.

BACKGROUND

Equipment such as, for example, agricultural machines, may have a fan.The fan may be used to create airflow. The airflow may be used forvarious purposes such as, for example, cleaning and cooling equipmentparts. The fan may be internal or external.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this disclosure, illustrate various embodiments of thedisclosure. In the drawings:

FIG. 1 is a diagram of a combine;

FIG. 2 is a diagram of a fan assembly;

FIG. 3 is a diagram of a fan; and

FIG. 4 is a cross-section of the fan.

DETAILED DESCRIPTION Overview

A fan may be provided. The fan may comprise a first plurality of vanesand a second plurality of vanes. The first plurality of vanes may bearranged substantially parallel to an axis of rotation and positionedalong a first arc substantially centered on the axis of rotation. Vanesin the first plurality of vanes may be being positioned at a first anglerelative to the first arc. The second plurality of vanes may be arrangedsubstantially parallel to the axis of rotation and positioned along asecond arc substantially centered on the axis of rotation. Vanes in thesecond plurality of vanes may be positioned at a second angle relativeto the second arc. The first angle may be different than the secondangle.

Both the foregoing general description and the following detaileddescription are examples and explanatory only, and should not beconsidered to restrict the disclosure's scope, as described and claimed.Further, features and/or variations may be provided in addition to thoseset forth herein. For example, embodiments of the disclosure may bedirected to various feature combinations and sub-combinations describedin the detailed description.

EXAMPLE EMBODIMENTS

The following detailed description refers to the accompanying drawings.Wherever possible, the same reference numbers are used in the drawingsand the following description to refer to the same or similar elements.While embodiments of the invention may be described, modifications,adaptations, and other implementations are possible. For example,substitutions, additions, or modifications may be made to the elementsillustrated in the drawings, and the methods described herein may bemodified by substituting, reordering, or adding stages to the disclosedmethods. Accordingly, the following detailed description does not limitthe invention. Instead, the proper scope of the invention is defined bythe appended claims.

An agricultural machine (e.g. a combine) may include a fan. The fan maybe used to create airflow. The airflow may be used for various purposessuch as, for example, cleaning and cooling equipment parts. Withembodiments of the disclosure, the fan may produce a pulsating airflowpattern.

Fans may comprise vanes (e.g., fan blades or airfoils). Withconventional fans, the vanes may all be positioned at a single angle.This may produce a steady air stream at a constant velocity. At varioustimes, however, it may be desirable for a fan's outlet airflow patternto pulsate. Consistent with embodiments of the disclosure, to achieve apulsating airflow, while maintaining a constant fan speed, the vanes maybe positioned at different angles. Velocity inconsistencies in the fan'soutlet airflow pattern (i.e., pulsation) may be adjusted by increasingor decreasing the angle differences amongst the various vanes. In otherwords, the angles between the various vanes may be constant oradjustable. For example, the airflow pattern produced by the fan may beadjusted by adjusting the various angles between the various vanes. Inaddition, the various angles between the various vanes may be adjustablein real-time (i.e., when the fan is rotating) or when the fan isstationary (i.e., when the fan is not rotating).

FIG. 1 is a diagram of a combine 100. Combine 100 may comprise aseparator housing 102, an operator's work station and cab 104, a graintank 106, and an elevator assembly 108. A swingable unloading augerassembly 110 may pivot to a position extending laterally outward to oneside of combine 100 to unload grain tank 106. Unloading auger assembly110 may swing inward to a storage position as shown in FIG. 1 when graintank 106 is not being unloaded.

Elevator assembly 108 may have a conveyor 112 mounted in an elevatorhousing 114. Conveyor 112 may be trained around rear drive sprockets 116and a front drum 118. Hydraulic linear actuators 120 may pivot elevatorhousing 114 to raise and lower the forward end of elevator housing 114.

Crop material may be fed to a feed beater 122 by conveyor 112 inelevator housing 114. Feed beater 122 may feed crop material to aseparating rotor 124. Separating rotor 124 may comprise a feed section126, a threshing section 128, and a separation section 130. Feed section126 may move crop material in a spiral path about a generally horizontalfore and aft axis of rotation to separating rotor 124, toward threshingsection 128. In threshing section 128, crop material may pass between acylinder bar 132 and a concave 134 where grain may be threshed. Threshedgrain that is not separated by concave 134 may be separated inseparation section 130 and may pass through a separation grate 136. Agrain pan 138 may convey grain and chaff forward and may deposit it on achaffer 140. Crop material other than grain (MOG) may be discharged fromseparating rotor 124 through a rotor discharge 142.

Grain and MOG that may pass through concave 134 and separation grate 136may fall to upper grain pan 138. Grain pan 138 may convey grain andchaff forward and may deposit it on chaffer 140. The grain may becleaned by chaffer 140 and a sieve 144 and air from a fan assembly 146.Chaff may be discharged from the rear of sieve 144 and chaffer 140.Clean grain may fall into a clean grain auger 148. The clean grain maybe conveyed to grain tank 106 by clean grain auger 148 and an elevator(not shown). Tailings may fall into a returns auger 150 and may beconveyed to separating rotor 124 by returns auger and return elevators(not shown), where they may be threshed a second time.

FIG. 2 is a diagram of fan assembly 146. Fan assembly 146 may comprise aduct 202 and a fan 204. Duct 202 may comprise a wall 206. Wall 206 maydefine a passage and/or a cavity 208. Fan 204 may be located in cavity208. Cavity 208 may be in fluid communication with an inlet 210 and anoutlet 212. Outlet 212 may be arranged to allow a fluid (e.g., air) tobe at least partially directed toward sieve 144.

FIG. 3 is a diagram of fan 204. Fan 204 may comprise a first section 302and a second section 304. First section 302 and second section 304 maybe separated by a mounting member 306. First section 302 may comprise afirst band 308 and a second band 310. Second section 304 may comprisesecond band 310 and a third band 312. First section 302 and secondsection 304 may be centered on an axis of rotation 314.

First section 302 and second section 304 may comprise any number ofvanes from a plurality of vanes 316. Plurality of vanes 316 may bearranged substantially parallel to axis of rotation 314. In addition,first band 308 and second band 310 may be absent in various embodiments.For example, plurality of vanes 316 may be attached directly to mountingmember 306. Mounting member 306 may be orthogonal to axis of rotation314.

While FIG. 3 shows plurality of vanes 316 located at one location alongaxis of rotation 314, embodiments may comprise plurality of vanes 316located at varying positions along the axis of rotation. For example,the vanes located in first section 302 may be located a first distancefrom mounting member 306 and the vanes located in second section 304 maybe located a second distance from mounting member 306. In addition, thevanes located in first section 302 may have a different length than thevanes located in second section 304. Furthermore, the various vanescomprising plurality of vanes 316 may have similar geometries ordiffering geometries. Examples of geometries may include a flat profile,a concave profile, a convex profile, and an airfoil profile. Forinstance, the vanes located in first section 302 may have a concaveprofile and the vanes located in second section 304 may have a convexprofile.

FIG. 4 is a cross-section of fan 204. To avoid cluttering FIG. 4 onlyeight vanes are shown. However, embodiments may comprise any number ofvanes. The vanes may be positioned at differing angles with respect to aplurality of arcs (e.g., a first arc AB, a second arc BC, a third arcCD, and a fourth arc DA).

First arc AB may comprise a first plurality of vanes (represented by afirst vane 402 and a second vane 404). The first plurality of vanes maybe positioned at a first angle α relative to first arc AB. Second arc BCmay comprise a second plurality of vanes (represented by a third vane406). The second plurality of vanes may be positioned at a second angleβ relative to second arc BC. Third arc CD may comprise a third pluralityof vanes (represented by a fourth vane 408, a fifth vane 410, and asixth vane 412). The third plurality of vanes may be positioned at athird angle θ relative to third arc CD. Fourth arc DA may comprise afourth plurality of vanes (represented by a seventh vane 414 and aneighth vane 416). The fourth plurality of vanes may be positioned at afourth angle φ relative to fourth arc DA.

While FIGS. 3 and 4 show first arc AB, second arc BC, third arc CD, andfourth arc DA having different lengths, embodiments may comprise arcs ofequal length. For example, first arc AB may occupy quadrant I, secondarc BC may occupy quadrant II, third arc CD may occupy quadrant III, andfourth arc DA may occupy quadrant IV. In addition, fan 204 may containany number of arcs. Furthermore, a radial distance of each arc may bedifferent. For example, first arc AB may be located a first distance(e.g., six-inches) from axis of rotation 314 and second arc BC may belocated a second distance (e.g., nine-inches) from axis of rotation 314.

Furthermore, first angle α, second angle β, third angle θ, and fourthangle φ may be fixed or adjustable. For example, fan 204 may comprisefirst arc AB occupying quadrants I and II and having a plurality ofvanes at first angle α. Fan 204 also may comprise second arc BCoccupying quadrants III and IV and having a plurality of vanes at secondangle β.

A vane's angle relative to an arc may be adjustable. Moreover, firstangle α, second angle β, third angle θ, and fourth angle φ may beadjusted and may cause an airflow exiting outlet 214 to have anoscillating velocity profile. In other words, the airflow exiting outlet214 may pulsate. For example, first angle α, second angle β, third angleθ, and fourth angle φ may be adjusted prior to using combine 100 toachieve a desired airflow pattern. In addition, first angle α, secondangle β, third angle θ, and fourth angle φ may be adjusted while combine100 is in use to achieve a desired airflow pattern or to change from afirst airflow pattern to a second airflow pattern.

An embodiment may comprise an apparatus. The apparatus may comprise afirst plurality of vanes arranged substantially parallel to an axis ofrotation. The first plurality of vanes may be positioned along a firstarc substantially centered on the axis of rotation. In addition, the fanmay comprise a second plurality of vanes arranged substantially parallelto the axis of rotation. The second plurality of vanes may be positionedalong a second arc substantially centered on the axis of rotation. Thevanes in the first plurality of vanes may be positioned at a first anglerelative to the first arc. The vanes in the second plurality of vanesmay be positioned at a second angle relative to the second arc. Thefirst angle may be different than the second angle.

Another embodiment may comprise an apparatus. The apparatus may comprisea combine having a sieve and a fan arranged to direct a gas at leastpartially toward the sieve. The fan may comprise a first plurality ofvanes arranged substantially parallel to an axis of rotation. The vanesin the first plurality of vanes may be positioned a first radius fromthe center of the axis of rotation. The fan may also comprise a secondplurality of vanes arranged substantially parallel to the axis ofrotation. The vanes in the second plurality of vanes may be positioned asecond radius from the center of the axis of rotation. The vanes in thefirst plurality of vanes may be positioned at a first angle of attackand the vanes in the second plurality of vanes may be positioned at asecond angle of attack. The first angle of attack may be different thanthe second angle of attack.

Yet another embodiment may comprise a method. The method may comprise:rotating a first plurality of vanes about an axis of rotation, rotatinga second plurality of vanes about the axis of rotation, and creating adesired airflow pattern in response to rotating the first plurality ofvanes and the second plurality of vanes about the axis or rotation. Thefirst plurality of vanes may be arranged at a first angle relative tothe axis of rotation. The second plurality of vanes may be arranged at asecond angle relative to the axis of rotation. The second angle relativeto the axis of rotation may be different than the first angle relativeto the axis of rotation.

Both the foregoing general description and the following detaileddescription are examples and explanatory only, and should not beconsidered to restrict the invention's scope, as described and claimed.Further, features and/or variations may be provided in addition to thoseset forth herein. For example, embodiments may be directed to variousfeature combinations and sub-combinations described herein.

All rights, including copyrights, in the code included herein are vestedin and the property of the Applicant. The Applicant retains and reservesall rights in the code included herein, and grants permission toreproduce the material only in connection with reproduction of thegranted patent and for no other purpose.

While the specification includes examples, the invention's scope isindicated by the following claims. Furthermore, while the specificationhas been described in language specific to structural features and/ormethodological acts, the claims are not limited to the features or actsdescribed above. Rather, the specific features and acts described aboveare disclosed as example embodiments.

What is claimed is:
 1. An apparatus comprising: a first plurality ofvanes arranged substantially parallel to an axis of rotation andpositioned along a first arc substantially centered on the axis ofrotation, the vanes in the first plurality of vanes being positioned ata first angle relative to the first arc; and a second plurality of vanesarranged substantially parallel to the axis of rotation and positionedalong a second arc substantially centered on the axis of rotation, thevanes in the second plurality of vanes being positioned at a secondangle relative to the second arc, the first angle being different thanthe second angle.
 2. The apparatus of claim 1, wherein the first arc andthe second arc form part of a same circle.
 3. The apparatus claim 1,wherein the first plurality of vanes and the second plurality of vaneshave different positions along a length of the axis of rotation.
 4. Theapparatus of claim 1, further comprising a mounting member substantiallyorthogonal to the axis of rotation, the first plurality of vanes and thesecond plurality of vanes operably coupled to the mounting member. 5.The apparatus of claim 1, further comprising: a duct having a wall, thewall defining a passage; an inlet in fluid communication with thepassage; and an outlet in fluid communication with the passage, whereinthe first plurality of vanes and the second plurality of vanes arearranged to propel a fluid into the inlet.
 6. The apparatus of claim 5,further comprising a housing having an inter surface, the interiorsurface defining a cavity and an exhaust, the exhaust in fluidcommunication with the inlet, the first plurality of vanes and thesecond plurality of vanes are arranged substantially inside the cavity.7. The apparatus of claim 1, further comprising a third plurality ofvanes arranged substantially parallel to the axis of rotation andpositioned along a third arc substantially centered on the axis ofrotation, the vanes in the third plurality of vanes being positioned ata third angle relative to the third arc, the third angle being differentthan the first angle and the second angle.
 8. The apparatus of claim 1,wherein the first angle relative to the first arc is configured to beadjustable and the second angle relative to the second arc is configuredto be adjustable.
 9. The apparatus of claim 1, wherein the first anglerelative to the first arc and the second angle relative to the secondarc are configured to cause an airflow pattern to pulsate.
 10. Anapparatus comprising: a combine having a sieve; and a fan arranged todirect a gas at least partially toward the sieve, the fan comprising: afirst plurality of vanes arranged substantially parallel to an axis ofrotation, the vanes in the first plurality of vanes positioned a firstradius from the center of the axis of rotation, the vanes in the firstplurality of vanes being positioned at a first angle of attack; and asecond plurality of vanes arranged substantially parallel to the axis ofrotation the vanes in the second plurality of vanes positioned a secondradius from the center of the axis of rotation, the vanes in the secondplurality of vanes being positioned at a second angle of attack, thefirst angle of attack being different than the second angle of attack.11. The apparatus of claim 10, wherein the first radius is substantiallyequal to the second radius.
 12. The apparatus claim 10, wherein thefirst plurality of vanes and the second plurality of vanes havedifferent positions along a length of the axis of rotation.
 13. Theapparatus of claim 10, further comprising a mounting membersubstantially orthogonal to the axis of rotation, the first plurality ofvanes and the second plurality of vanes operably coupled to the mountingmember.
 14. The apparatus of claim 10, further comprising: a duct havinga wall, the wall defining a passage; an inlet in fluid communicationwith the passage; and an outlet in fluid communication with the passage,wherein the fan arranged to direct the gas at least partially toward thesieve comprises the fan arranged to direct the gas into the inlet,through the passage, and out the outlet, the outlet arranged to directthe gas at least partially toward the sieve.
 15. The apparatus of claim14, further comprising a housing having an inter surface, the interiorsurface defining a cavity and an exhaust, the exhaust in fluidcommunication with the inlet, the fan located substantially inside thecavity.
 16. The apparatus of claim 10, further comprising a thirdplurality of vanes arranged substantially parallel to the axis ofrotation and positioned along a third radius from the center of the axisof rotation, the vanes in the third plurality of vanes being positionedat a third angle of attack, the third angle of attack being differentthan the first angle of attack and the second angle of attack.
 17. Theapparatus of claim 10, the first angle of attack and the second angle ofattack are configured to cause an airflow pattern to pulsate.
 18. Amethod comprising: rotating a first plurality of vanes about an axis ofrotation, the first plurality of vanes arranged at a first anglerelative to the axis of rotation; rotating a second plurality of vanesabout the axis of rotation, the second plurality of vanes arranged at asecond angle relative to the axis of rotation, the second angle relativeto the axis of rotation being different than the first angle relative tothe axis of rotation; and creating a desired airflow pattern in responseto rotating the first plurality of vanes and the second plurality ofvanes about the axis or rotation.
 19. The method of claim 18, whereincreating the desired airflow pattern comprises creating a pulsatingairflow pattern.
 20. The method of claim 18, wherein creating thedesired airflow pattern comprises creating a uniform airflow pattern.